An image forming apparatus is an apparatus for generating an image on a print medium. Representative examples include a printer, a copier, a facsimile, a scanner, and a multifunction printer that integrally implements these functions.
An image forming apparatus may include a door provided on one side of a body. By opening the door, a user may access a toner cartridge tray that is mounted to be movable inside and outside of the body of the image forming apparatus. The toner cartridge tray may support a plurality of developing units such that, if a developing unit runs out of a developer, a user may open the door and extend the toner cartridge tray outside of the body to replace or refill the developing unit. The toner cartridge tray may slide on a guide rail, provided inside the image forming apparatus, to be moved inside and outside of the body.